ARM: dts: omap3/4/5/dra7: remove unneeded unit name for gpio-leds nodes

This patch fixes the following DTC warnings for many boards:

"Node /leds/led@1 has a unit name, but no reg property"

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/dra7-evm.dts

@@ -105,25 +105,25 @@
 
 	leds {
 		compatible = "gpio-leds";
-		led@0 {
+		led0 {
 			label = "dra7:usr1";
 			gpios = <&pcf_lcd 4 GPIO_ACTIVE_LOW>;
 			default-state = "off";
 		};
 
-		led@1 {
+		led1 {
 			label = "dra7:usr2";
 			gpios = <&pcf_lcd 5 GPIO_ACTIVE_LOW>;
 			default-state = "off";
 		};
 
-		led@2 {
+		led2 {
 			label = "dra7:usr3";
 			gpios = <&pcf_lcd 6 GPIO_ACTIVE_LOW>;
 			default-state = "off";
 		};
 
-		led@3 {
+		led3 {
 			label = "dra7:usr4";
 			gpios = <&pcf_lcd 7 GPIO_ACTIVE_LOW>;
 			default-state = "off";